First off, I totally understand your fear and I am so sorry you are having to deal with it. I've had a tons of anxiety this pregnancy and I wouldn't wish it on anyone.
Different people process hCG differently. You can have MUCH higher levels in your blood than your pee. It all depends on what your kidneys are doing and how much of the hCG your body is using. It is totally possible to get a 2-3 weeks reading on a digi at 6-7 weeks. Also, hpts are stupid. The results can depend on how much water you drink, you body's personal circadian rhythm cycle, any vitamins/meds you're on, etc, etc, etc.
My test line at hcg = 5,000 was only half as dark as it was when my hcg = 2,500. Scared me so bad that I ran to the ER. Ultrasound and hcg blood work showed everything was fine and doctor said to STOP PEEING ON STICKS. He said the hpt's are TERRIBLE at showing progression after more than the first week or so. I haven't take one since.
I know nothing I say will take away the fear, but remember that you're not bleeding/cramping and you do have a positive test. That's what matters. I would honestly recommend stopping the POAS thing at this point. The stress those tests cause is no really awful, and if they're stopping you from enjoying your pregnancy, that's no good.